The phrase "even hypothetically" is correct and can be used in written English.
It is typically used to emphasize the impossibility or unlikelihood of something, even in a hypothetical scenario. Here is an example: "Even hypothetically, it is impossible for a human to survive without water for more than a few days."
Even hypothetically it's too much effort.
They do not seek to make a profit, even hypothetically.
Davis dismissed the idea that speaking even hypothetically about a cut-off date for residency rights could spark a movement of people to the UK.
Maybe I had fallen in love, but with little consciousness of it: what I mean is, I did not admit it to myself, not even hypothetically.
His team has talent, but not enough to even hypothetically warrant a playoff spot, and certainly not enough to overcome their collective lack of focus.
When the president's top economist suggests, even hypothetically, considering hamburger-flipping a form of manufacturing, it's a golden opportunity to accuse the White House of being out of touch with the concerns of working Americans.
The mere fact that my French friends raise the question, even very hypothetically and three-quarters-jokingly, is a sign of the times.
People's experiences of themselves and of other people are subject to all kinds of sampling biases that would be difficult to correct for, even if (hypothetically) their thinking were perfectly unbiased and entirely realistic.
"Even if, hypothetically, that position changed and he was sold, what would the replacement cost be?
Even if, hypothetically, the U.S. took the zany decision to arm ISIS against Assad, the results would probably help Assad on balance.
Even though, hypothetically, antisubmarine aircraft could fly out of Hokkaido on the prowl for subs, that's a far different matter from letting US subs into the bastion to hunt at will.
